杏吧原创

DINOSAURS really did go out with a bang, say researchers in Wisconsin. While
many palaeontologists think a meteorite impact 65 million years ago led to the
great reptiles鈥� abrupt demise, others claim that the creatures were already on
the verge of extinction, citing a supposed lack of dinosaur fossils in rocks
laid down in the 2 million years preceding the impact. But a team led by Peter
Sheehan of the Milwaukee Public Museum has found several fossils in this layer
in the Hell Creek Formation in the upper Great Plains of North America. 鈥淭he
evidence is consistent with an abrupt extinction event,鈥� Sheehan says in
Geology (vol 28, p 523).